UIActivityViewController in Swift Crashes on iPad

The UIActivityViewController's has non-null popoverPresentationController property when running on iPad. So, try below.

if let wPPC = activityVC.popoverPresentationController {
    wPPC.sourceView = some view
    //  or
    wPPC.barButtonItem = some bar button item
}
presentViewController( activityVC, animated: true, completion: nil )

Building on @Satachito's answer: As the sourceView you can create an (invisible) CGRect at the place the popup should point to, and set the arrow in that direction:

let activityVC = UIActivityViewController(activityItems: objectsToShare, applicationActivities: nil)

if UIDevice.current.userInterfaceIdiom == .pad {
    activityVC.popoverPresentationController?.sourceView = UIApplication.shared.windows.first
    activityVC.popoverPresentationController?.sourceRect = CGRect(x: 0, y: 0, width: 300, height: 350)
    activityVC.popoverPresentationController?.permittedArrowDirections = [.left]
}

UIApplication.shared.windows.first?.rootViewController?.present(activityVC, animated: true, completion: nil)